Flexible tubular corrugated metal wall.



W. M. FULTON.

FLEXIBLE TUBULAR GORRUGATBD METAL WALL.

APPLIOATION FILED MAY 19, 1913.

Patented May 12, 1914.

- To all 'w71 om 'it may concern.'

-msuTEn sTaTEs EATENT cEETcE.

WESTON M. FULTON, or KNoXvILLE, TENNESSEE, ASSIGNOE To THE FULTON OOM- EANY, OE KNOXvILLE, TENNESSEE, A CORPORATION OE MAINE.

FLEXIBLE TUBULAR CORRU'GATED METAL WALL.

spcification of Letters Patent.

` Applieation inea May 19,l 1913. serial No. 768,624.,

rai-,antec May i2, iam.

Be it known that lI, WEs'ipN M. FUL'ioN, of Knoxville, Tennessee, have invented a 'new andA useful Improvement in Flexible Tubular Corrugated Metal Walls, which invention isfully set forth in the following specication.

This invention relates to "flexible tubular corrugated metal walls for confining fluids. -Vibratory tubular walls have heretofore been made in one of two general ways, either the wall has been built up of flat annular disks soldered or brazed to each other at their edges ora tube .was provided with cor rugations suiicien'tly deep to give to the wall the requisite flexibility. In the disk construction, flexibility was secured by making the width of thev annular part quite wide. Whether the meeting edges lof the disks were brazed flat together or .bent into curved lapped joints, it was found that the joints did not stand up under the vibratory movements of the wall and cracked apart. The width of the disks introduced buckling difficulties resulting in lost motion in the extension and contraction of the wall` and eXtra wear on the disks. In the corrugated construction circumferential joints' have been avoided and flexibility secured at the bends aswell asin the connecting portions between th'e bent portions of the wall.' This construction has also enabled the narrowing of the connecting portions and thereby avoiding in largemeasure buckling dificulties in these portions'. While these advantages have l.been secured bythe introduction of the flexible corrugated wall, disadvanltages have been introduced especially in,

those situations in which the flexible Awall is used to contain an-expansible fluid, the liuc- Y tuations of pressure of which on thewalls causes the vibratory movement of the wall.

Inpractice, I the lateral pressure of such fluid on the wall perpendicular to the axis.

of thetubular wall becomesVv at times excessive and has resulted inthe use of non-lientl ble braces which 4are applied.v in the form of .rings on the concave side of the bends.

Such practice 4is illustrated-in U. S. Patentv 893,382. For the same purpose the convex sides of the bends have received like braces which are recessed to receive the crests of thebends. While these devices overcome the outward pressure of the iuid'in the ves sel, no account has been taken in their use ent forms of their effect on the bending strains in the vicinity of the Wall where they are located.

The extension and contraction of a corru-` gatedmetal wall is accompanied by changes 1n the radius of curvature of the bends. The presence of rigid braces eitherl on the concave or on the convex side of the bends locallzes these -bending strains along narrow lines -where the wall bends yat the brace. Their presence accentuates the Wear at the bends in the wall and hastens deterioration at these Iconcave and convex portions.

My invention relates toflexible tubular walls provided with corrugationsand particularly to improvements in meansl for lbra'clng the concave and convex portions against outwardly exerted fluid pressurewhile giving-to the said curved portions a vdurability equal that of the lateral portions of the wall connecting-thaconcave and con-y veX portions, and my invention accom- ,plishes the'above objects by associating with x those. portions ofl the iexible 'corrugated wall constituting the bends, resilient members adapted t0 reinforcethe bends against.-

fluid pressure forcing them outward and to yieldingly restrain the lexure of the` bends in their vibratory movement either in one direction or both directions with respect to their position of rest and thereby more equally distribute 'the .working strains between the curved portions andlateral portions of the wall and increase the durability of the wall. Y e

My invention is capable of mechanical expression in various forms some of which are illustrated infthe accompanying ldrawings which Lare intended as illustrations lto`assist the description and not asdeining the limits thereof.

In the drawings Figure 1 is a view in central vertical Asection showing a iieXible corrugatedwall provided with myimprovev ment. Fig. 2 is a horizontal sectional view taken on line Q-Qof Iig. 1. Figs. 3 and 4: are detaill views highly magnified. Figs. 5,

6,7 and 8 arc\detail views highly magnified, showing portions ofbends to which difer-j.

of my improved brace 'are applied. A y' Referring to Figs. vl, 2, 3 vand 4 of the drawings, a flexible tubular corrugated wall `is therein shown, the bends Tof. which are provided on their convex. surfaces with braces Imade 'of highly resilient material,

' practice,

such as thin sheet brass, steel or the like. In the drawings, the thickness of the metal comprising the walls and braces is somewhat enlarged for the sake of distinctness. In very thin metal is used andseldom not more than one one-hundredth of an inch in thickness. These braces conform to the shape of the bends and preferablyoverlap the marginal surfaces of the portions2 of the wall which connect the oppositely curved portions forming the bends of the corrugations. Figs. 1-4, gradually'rincreased flexibility is given the margins of the'braces 1 by providing the margins where they extend over the connecting portions 2, with serrations 3. The resiliency of the braces l is thus graduated along their margins to the ldegrees of flexure of the bends where the latter merge into the lateral connecting portions 2 of the wall', thereby avoiding along these lines sharp lines of wear and more equally distributing the strains between the curved portions and the lateral connecting portions of the wall during its vibratory movements and also movements from side to side of its longitudinal axis. In Fig. 4, a fragment of the corrugated wallv is shown while its bend is at the outward limit of an expansion af of the vesselY and while the bend is passing 'through its normal position of rest, b. In

the position, a, of expansion, the curved portion of the wall and the brace member increase their radii of curvature and a slight slip takes place between the parts. The resilient margin or serration 3 reinforces the bend where it merges into the connecting yportion 2 and transfers part of the bending strains heretofore sustained by the metal in the bend where no brace or where an inflexible brace has been used to the connecting portion. The work is thus more evenly divided between these two elements of the wall with evident advantages. During the con'- tracting movement of the flexible wall the brace participates in the movementof the surface in contact with itand owing to the marginal resiliencyof the brace continues in contact with the wall to the position of rest b, thereby hugging the wall in its move-v ments'and excluding dirt and moisture from between the surfaces.

' In Figs.. 6 and 7, a modified form ofre.

silient brace is shown. Instead of serrating the margin, the margin is unbroken in outline and thinned down at 4 and vanishes to an edge. It will be apparent from what has been explained above in respect to the serrated form of brace that this form accomplishes the same results and in substantially the same manner.

' In Fig. 8 is shown a flexible brace in all respects like the two forms previously described except that serrations and the thinned margin are omitted. While this In the form of brace illustrated inform does not participate in all the advantages possessed by the other forms in the matter of flexibility, yet it embodies the idea of means for reinforcing the flexible bends of a corrugated metal wall with a resilient brace which is within the scope of my invention.

While I have so far described my improvement as 4applied to the convex surfaces of the 4bends in the flexible wall, I may apply the flexible brace in any of its forms to either side or to both thevconvex side and concave side. This construction is illustrated in Fig. 5 in which a serrated brace l is shown. on the convex surface of the bend and a similar brace '1' is shown as'placed against the concave surface. The principle of construction is the same for both forms.

The material of the braces is preferably the same as that of which the walls of the tube are made, yet it is to be understood that the wall and braces may be of different material.

It will be observed that all forms of my resilient brace secure protection of the circumferential curved portions of the wall against internal pressures. while having the other advantages peculiar to their construction as above pointed out. l

While I have described my invention as peculiarly applicable to tubular corrugated walls, I do not desire to limit my application to such'walls since it is applicable to other forms of corrugated walls such as flat bends of flexible corrugations are subject to flexure back and forth.

Vhat Ik claim is 1. In combinat1on,'a flexible corrugated of said corrugations and adapted to equalize the strains at the bends with those in portions of the wall between said bends.

2. In combination, a flexible corrugated wall and resilientmeans associated with'the bends in said wall for resisting their flexure.

3. In combination, a flexible wall composed of bent portions united by lateral portions and resilient means applied to said bends and said lateral portions.

4. In combination, a flexible corrugated wall and braces having flexible margins associated with the bends in said wall.

5. In combination, a flexible corrugated wall and braces having serrated resilient margins associated with the bends in said wall.

6. In combination, a flexible tubular wall provided with corrugations and braces engaging the bends of said corrugations and having serrated flexible margins extending beyond said bends.

7. In combination, a flexible tubular metal wall provided with corrugations and resilient braces associated .with the convex surcorrugated flexible walls and wherever the j wall and flexible braces located at the bends j faces of said corrugations restraining the In testimony whereof I have signed this ieXure of said corrugations in onedirection. specification in the presence of two subscrib- 8. In combintion, a flexible tubular metal ing Witnesses.

` WESTONM. FULTON.

Wall provided with corrugations and braces n 5 engaging the ben/ds of said corrugations and Witnesses:

having exible margins extending beyond C. H. BROWN, Jr., the bends. I. A. MARTIN.` 

